Pickup arm



Oct. 11, 1932. J. RABER 1,881,942

' PICK-UP ARM Filed Ma 22, 1931 Fig.1.

I N VENTOR.

Jo eph Haber;

Patented Oct. 11, 1932 warren stares QPATENT'VTQFFICEHY JOSEPH BABER, orHADDONFIELD, NEW JERSEY, Assielvoa, BY MESNE ASSIGNMENTS, ro nameccaronATior-i or mansion, on NEW YonK,,n. Y., A cortroaa'rion'orDELAW'ABE PICKUP ARM Application filed May 22, 1931. Serial No. 539,310;

-The present invention vrelates to electric sound translatlng apparatusand more particularly to a unitary part thereof which may be termed thesound translating unit. Such a' unit includes the 61601311? soundtranslatingdevice, or electric pickup, and the suspension meanstherefore, by which it is 'mountedin the sound translating apparatus andpermitted to move in operating relation to thesound record.

A unit of the above character provides for carryingthe electric pickupdevice at one end of a beam or arm which is pivotally mounted adjacentits opposite end in a suitable swivel pedestal or supporting means andthearm is suitably counterweighted to compensate for the weight of thepickup device and provide the desired pressure of the stylus of thepickup device upon the record or sound I track.

Sound translatingunits ofthis character known heretofore have assumedvarious forms and have embodied a varlety of mounting means for thesupporting arm or beam I requiring a relatively large clearance space inthe cabinet structure of the apparatus, for properoperation. a

It is an object of the present invention to provide an improved electricsound translating unit of the type embodying an electric soundtranslating dev1ce,-a suspension arm and a supporting pedestal therefor,which, while permitting full operat ng movement oi the tranlatin device,is of compact construc- I tion adapted to operate in a space of greatlyreduced dimensions from that heretofore known. V I

1t 15 a further ob ect of the present invention to pro *ide an electricsound translating unit of the above character, the elements ofv whichare arranged to provide for easier operation and which have an improvedoperating characteristic.

The invention wlll, however, be better un- In the drawing Fig; 1 isaview inperspec} J tive on a reduced scale of an electrical soundtranslating unit embodying the invention; Fig-.2 1s a crosssectionalviewionlthe same scale of a portion ofthe' unit shown in- Fig.1,

further illustrating the construction there: of Fig. Sisa crosssectional view of a portion of the unit shown in 2 taken on the sectionline 3+3; Fig. 4 is a cross sectionalview of the electricsoundjtranslating device or pickup; and F ig. 5 is a side view onsubstantially the same scale,of a modification of a portion oft-he unitshown in Figs, 2 and 3.

Referring to Figuresl, 2, 3, aud t of the drawing 8 is asoundtranslating device which mounted upon an elongated suspension arm9in turn supported by a swivel pedestal 10 provided with: a suitable.counter weight means 11 for the translating device. The pedestal ismounted ina sound translating apparatus 12 and is arranged'to carry thetranslating device 8 inoperating relation to a sound record 13WlthWhlOll, in Flgure 1,

the stylus 14 of thesoundtranslating device isshewn in operatingengagement.'-

The suspension arm is enlarged or flared at its end opposite thetranslating device and provided with flanged, edges 14 adapted toenclose the upper end of the pedestal 10, and

the counter weight means 11. The latter is a secured tothe arm and isarranged to lie-between two spaced parallel ears 15 provided upon thepedestal 10.

The axis of :rotation for the pedestal is provided by a central hollowpivot pin 16, and

substantially in alignment therewith amidst a right'angle thereto thereis provided a horizontalpivot axis'provided by a pivot pin 17 for'thesuspension arm about whichit may be moved-to lift'the translating devicefrom the record and to return it thereto. This op eration is necessaryfor changing records andfor changing the needle of the stylus 14 and Vis the usual pivot axis employed in known suspension means for soundtranslating devices of this character; 7 v a In the present example,however, and in accordance with the invention, there sgprovided a secondpivot axis or pivot pin :18 1

parallel with the firstand' spaced therefrom preferablyin advance of theaxis 16 andiin advance of the axis 17 toward the translating 16o.

device. 7 This axis is providedby a second pivot pin 18; This is coveredby a body of vibration absorbing material such as a sleeve or tube 19 ofrubber or other suitable resilient material. The pin 18 iscarried at itsends 1 and secured to the flanges 14 of the flanged portion ofthe'armand the sleeve 19 rests adjacent its ends in a saddle in thepedestal provided by parallel notches 20 in the ears 15. f Itwill beseen that the arm 9 may be lifted about the axis 17 whereby the pivotaxis 18 will be caused to move with the farm about i the axis 17. Thispermits advantage to be taken of the full length of. the suspension armweight is obtained, however, hy permitting thearm to pivot about theaxis 18 when the stylus of the translating device is in engagementwiththe record 13. This is provided by permitting a slight operatingmovement of the arm about the pivot axis 18 by the arrangement of thepivot axis 17 as indicated in the drawing. The pivot pin 17 is. carriedby the flanges 14 of the suspension arm 9 in the same manner as the pin18. The pin 1? is then journaled in the ears 15 in loose bearingsprovided-by enlarged openings or apertures 22in the ears, of a diametersuificient to permit'a slight movement of the arms about the pivot axis18 as the stylus of the translating device follows the irregularities inthe movement of the record surface in a vertical direction. V i

The suspension arm is thus arranged to rotate in a single plane abouttwo separate spaced parallel axes provided by two spaced parallel pivotpins 17 and 18 which in turn are at aright angle to the pivot pin 16 forthe pedestal. The pedestal is provided with a loose bearing for thepivot pin17 and a saddle 7 type of bearing for the pivotpin 18, thelatter being provided by extending the pedestal forwardly as indicatedmore clearly in the cross-sectional view: provided by Figure 2; Themovement of the arm about the axis 18 is such that when the arm .is inthe-operating position and the stylus is resting upon a record, as shownin Figure 1, the excess weight of the translating device upon the recordabove that desired for proper stylus pressure isJcounterbalanced' by theweight lltothe rear of pivot pin 18, and rotation takes place during therecord translation about the pivot pin 18. The difference in diameterbetween the pin 17 and that of the apertures or openings 22 in thepedestal provides suflicient play to permit the. stylus to accommodateitself to any vertical irregularity that may be encountered in thesurface of'the record. The pivot pin 20 and its resilient sleeve 19resting in the notches 20 may be'freely disengaged provided by the pin17.

'By the construction shown and described, whereby a separate pivot axisis employed for the translating process, the counter weight 11 may thusbe located in a more forward position over the pedestal 10 and hencetakes up a minimum of space to the rear. This weight is made effectiveby the change of the pivot axis. 7 I

It will be noted that the translating device and arm, including thecounter weight, lie in substantially a common horizontal plane passingsubstantially through the pivot axes 17 and 18. VJith this arrangement,asound translating unit of minimum height is obtained and as indicatedmore clearly inFigure 4 by providing that the axis of rotation 23 of thestylus 14ilies in the extension of the arm 9 and substantially in acommon plane therewith, an improved operatingcharacter istic is obtainedThis is for the reason that with the'axis 23 of the stylussubstantial'lyin the plane of the arm, a lesser torsional; vibrationis imparted to thearm by movement of the stylusf V I I In the present example, the stylusis'provided with an armature 24 located in an electrical pickup coil 25and provided with a suitable field magnet 26 and a cover means 27.

The pickup coil 25 is provided with output leads indicated at 28. Thisrepresents any suitable electrical-or other sound translating device,the general arrangement of which is such that it lies substantially incontinuation and in the plane of the suspension arm 9.

This construction has the advantage that,

as above mentioned, in height or vertical depth, the unit is reduced toa minimum dimension and lmproved response is provlded because of thereduction of torsional vlbration from the stylus being translated to thearm. 7

It should be noted that the stylus 14 is arranged to lie at an acuteangle with respect to the pivot axis 23. In operation, this arrangementprovides for smooth operation of the stylus in the record track and thatthe pivot axis 23 lies substantially parallel to the record surface. 1

Referring now to the modification shown in'Fig. 5, the two axescorresponding.respectively with'those defined by the pins .17 and 18, inFigs. 1, 2, and 3 are connected by a link ed through extension's'31,'bycross member 82. The pedestal 33,. onwhich a suspension arm 9vispivotally mounted, is provided at its'upper end with a yoke 34,havingspaced ears 85, (one of which is shown), andthe side members 30 arepivotallyconnected herewith.

by pivot pins 36, (one of. which is shown), and tothe arm by a pin 37.Thepins 36 define the axis of rotation corresponding to that defined bythe. pin 17 in Figs. 1, .2, and'3, and the pin defines the axiscorresponding to the axis as defined by the pin 18 in saidfig ures. Inthis construction, the pin 37 is not the pin 18 in Figs. 1, 2 and 3 andby the pin disengageable from the'link or'from the arm, the said linkbeing rotatable with the arm, in moving the stylus to and f'roin'piaying position.

The link 29 is held, in a horizontal position during the translation ofa record by abutment of the rear edge of the cross member 32 against theyoke 34:. There is no connection between the arm 9 and the pedestal onthe pivotal axis defined by the pins 36. In consequence, when the arm45is in playing position, allrotation will occur around the axis definedby the pin 87.

The moments about the pivotal point, definedby the pin 37 in Fig. 5, aresimilar to the moments described in connection with and coaxial with thelongitudinal axis of the. arm. Furthermore, two parallel pivot axes areprovided for the arm, one of which lies in' a more forward positiontoward the translating device with respect to the other, and that theseaxes'lie in the plane of the armin common with the counter weight'means. This arrangement reduces the space" required to the rear of thearm'f-or the reason that the counter welght is carried in a more forwardosition with respect to the main pivot axis. It should be noted that theaxis defined by 87 inFigc5, is located as far forward as practicabletoward the. translating device, to utilize a greater portion of the massof the arm as part of the counter weight structure whereby the moment onthe side of this axis toward the translating device above that requiredfor faithful tracking of the stylus in a record groove, and the mass ofthe counterweight, maybe reduced to a minimum. The

Figs. 1, 2, and 3, so that the counterbalance purposes may thusbe'materially. reduced as compared with commonly known construc-' tions.of this character and, in consequence, :the pro ect1on ofxthe arinrearwardly of. the pedestal may be minimized. time, zontal rotation ofthe unit about its vertical axis, as is desirable for faithfultranslation of" a recordis preserved. p

AlthoughI have shown and described cer- At the same the desiredlength ofthe radius of horiadded mass required for 'counterbalancingi v tainspecific embodiments of my invention,

I am :fully aware that'many modifications My invention, therei fore, isnotto be restricted except insofar as byuthe;

thereof are possible.

is necessitated by the prior art and spirit of the appended claims;

Iclaimas my invention: p

In an apparatus of th'efcharacter described, a-sound translating device,an -arm for supporting said device, a supporting means for the arm, a-ndvmeans providing spaced parallel of rotation between the arm and thesupport therefor, said arm being.

rotatable relative to the supporting-.means selectively about said axes.

l 2. In an apparatus of the characterdescribed, a fixed supportingpedestal, a sound translating device, an arm forisupporting said device,and means. providing space respect to said'pedestal, one of said axesjbeing arranged torotate about the other.

3. In an-apparatus of the. character described, a fixedsuportingpedestal, a sound translating device, an arm forsu-pportingsaid device, means providing spaced parallel axes ofrotation for saidarmawithrespect to saidpedestal, one ofsaid axes being arranged torotate about the otherfa movable stylus for said device, and meansproviding a pivot axis for said stylus substantially in the plane ofsaid armn 4; In an apparatus of the:character described, the combinationof a support, asound translating device, a suspension arm for saiddevice, and means providing substantially parallel axes of rotationfor'lsaid arm about said'support, said axes being so spaced and relatedthat the arm may be moved about one of said axes during soundtranslation, and

d parallel axes of rotation for said arm withabout-.the other inmoving'the translating device to or froma sound translating posi-v tion.v

5. In an apparatus of the character descrlbed, the combination of asupporting ped-' estal, a sound translating device, a suspension I armfor said translatmg device, said arm having a pair of pivotaxesabouteither of which selectively the arm is movable in the sameplane, and pivot means-for said arm arranged to permit movement of saidarm inia plane at zs angle to said first-named plane.- 7

1-6. In an pparat s {bf streamer de. 39-

scribed, the, combination of a pedestal, Ya sound translating device, asuspension arm for said translating device, said arm having a pair ofpivotaxes .about which the arm is -movable in substantially the sameplane, a

movable stylus for said device, and means providing a pivot axis forsaid stylus substantially inthe plane of the arm.

7". In combination, a sound translating de vice, a suspension armtherefor havinga longitudinal axis, a support for said arm, means provnga pair'of pivotaxes for the arm ar- 7 ranged to permit rotationalmovementof the arm with respect to the support, a stylus for thelongitudinal axisof said ar said device, and means providing a pivotaxis for said stylus substantlally coaxial wlth.

;8. In a device of the character described, an elongated SllSPQIlSlOIIarm, asound translating dev1ce secured .to said arm and having a bodylying substantially in the plane thereof, said device having a'movablearmature,

' and meansproviding a pivot axis for said said device.

armature lying substantially in extension of the:longitudinalaxis of thearm. V

9. In a sound translating apparatus, the

combination of a sound translating device, a

movable suspension armto which adjacent one end said devlce 1sconnected, means providing a horizontal axis of movement for said armatapoint along said arm, in spaced relaaxis for swinging the arm in ahorizontal direction, a horizontal pivot means arrangedto pivotallyconnect the arm and thepedestal to permit movement of the arm in avertical plane,a secondpivot means located between the first-named pivotmeansand said device,

- saidsecond-named pivot means being movable with respect to thepedestal in a vertical plane about the axis provided by said firstname-dpivot means.

' 11,.In a device of the character described,

a sound translating device, a suspension arm I therefor, a pedestal forsaid arm, means prowith said arm and extension viding a horizontalextension for the pedestal, 'meansproviding a pivotal connection betweenthe pedestal-and arm defining an axis .ofrotation for movement of thearm in a vertical plane, and means providing a second axis ofrotationfor the arm providing for movement of the arm in the same verticalplane, said last-named means being movable first-named axis. 7 r q 12.In a phonograph apparatus, a sound translating device, anarm'su'pporting said means about the device, means providing a pair ofpivotal? axes spaced along said arm about wh ch the arm is adapted tohave pivotal'movement se' lectively; one of said axes being more remotefrom thetranslating device than the other in a direction along said arm.V

' 13. The combination with a-sound translating device, of a. supportingarm therefor, said arm and 'device being arranged to lie in a commonplane, a supporting means for the armprovided with a pivot-axisperpendicular to said plane, means providing a. pivot axis between saidarm andsaid' su'pport'in the plane of the arm and at a right angle tothe first-named pivot axis, and means providing. a second pivot axisbetween the arm and the support.

14. A sound translatin unit' comnrisin in combination a soundtranslating device having a stylus adapted to engage arecord surface atan angle thereto and a. pivot axis for said stylus arranged to liesubstantially parallel. with a record surface when the stylus is inengagement therewlth in operatlon, a suspension arm for'the translatingdevice arranged to lie in a common plane with the axis of said stylus, asupport for the arm adapted to be pivotally mounted, and means providingtwo spaced parallel pivot axes for] the arm in connection with saidsupport.

15. A sound translating unit comprising in combination, a soundtranslating device,

a suspension arm therefor to which saiddevice is connected adjacent oneend, said arm and said device being arranged to lie substantially in acommon plane,ja supporting pedestal for the arm connected therewith inspacedrelation to the translating device, a

pair of spaced parallel pivot axes in said connection about which saidarm, is movable 1n the-same plane, and meansfor causing one of saidpivot axes to become effective as V a pivot axis for the armwhen in aplaying" position and for-the other pivot axis to become effective whenthe arm isin': a raised position from the playing position.

16. A sound translating-unit comprising 1n comblnation, a sound translatng device,

a suspension arm therefor, a counterweight means for said arm, anoperatingpivot axis forsaid; arm between said counterweight and saidtranslating device, and means for caus ing said pivot axis to shift to apredetermined position away from said translating device when said armis raised from the operating position.

In testimony subscribed my name this 19th r r JOSEPH RABER.

whereof, have hereunto day of May,

